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Hydrothermal Liquefaction of Wheat Straw in Sub-critical Water/Ethanol with Ionic Liquid for Bio-oil Production 被引量:2
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作者 Wang Baofeng Han Shaohua Zhang Jinjun 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2015年第4期81-88,共8页
Hydrothermal liquefaction of wheat straw in sub-critical water with ionic liquid was investigated in an autoclave. The product distribution at different temperatures and pressures was studied. The liquid oil and the r... Hydrothermal liquefaction of wheat straw in sub-critical water with ionic liquid was investigated in an autoclave. The product distribution at different temperatures and pressures was studied. The liquid oil and the residuals were tested by 1H NMR, FTIR and SEM techniques. The results indicated that under the same conditions, the oil yield from liquefaction of wheat straw in water/ethanol was higher than that in sub-critical water. The result also showed that under the investigated conditions, adding 1-butyl-3-methylimidazolium chloride([Bmim]Cl) could increase the total conversion and gas yield, while at the same time the yield of n-hexane insoluble fraction and the tetrahydrofuran soluble fraction was reduced. Moreover, the results also showed that upon adding [Bmim]Cl the contents of the aliphatic hydrogen and phenols in liquid oil also increased along with improved oil quality. 展开更多
关键词 wheat straw liquefaction sub-critical water ionic liquid
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Co-liquefaction of Cotton Seed and Flos Populi in Sub-critical Water/Ethanol Solvent for Bio-oil with Medical Stone Based Additives
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作者 Wang Baofeng Yan Xiaomin Cheng Fangqin 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2020年第3期56-64,共9页
The co-liquefaction behaviors of cotton seed(CS)and flos populi(FP)were investigated in the sub-critical water/ethanol mixed solvent using the medical stone(MS)based additives.Oil products were characterized using FTI... The co-liquefaction behaviors of cotton seed(CS)and flos populi(FP)were investigated in the sub-critical water/ethanol mixed solvent using the medical stone(MS)based additives.Oil products were characterized using FTIR,GC-MS,1HNMR,and 13CNMR techniques.The test results showed that the synergistic effect of co-liquefaction was obvious when the ratio of cotton seed and flospopuli was 1:1 without additives.The additives,such as 12-phosphotungstic acid(PW12),HZSM-5,PW12/HZSM-5 and modified medical stone(MS),PW12/MS,Ni/MS,Co/MS,Mo/MS and Co-Mo/MS,could increase the bio-oil yield;and the modified MS resulted in higher liquefied oil yield than that achieved by MS.Furthermore,additives such as Ni/MS,Mo/MS,and Co-Mo/MS also could increase the yield of aliphatic hydrocarbons in liquefied oil.The addition of Co-Mo/MS could lead to a highest liquefied oil yield of 28.8%,while the additive of PW12/HZSM-5 could result in a highest total conversion of 81.6%.Results also revealed that additives,such as PW12/MS,PW12,PW12/HZSM-5,Ni/MS,Co/MS,Mo/MS,and Co-Mo/MS,could increase the H2 production and decrease the CO2 production in gas products. 展开更多
关键词 cotton seed flospopuli sub-critical water/ethanol CO-LIQUEFACTION BIO-OIL
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The emerging role of mesenchymal stem cell-derived extracellular vesicles to ameliorate hippocampal NLRP3 inflammation induced by binge-like ethanol treatment in adolescence
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作者 Susana Mellado María JoséMorillo-Bargues +4 位作者 Carla Perpiñá-Clérigues Francisco García-García Victoria Moreno-Manzano Consuelo Guerri María Pascual 《Neural Regeneration Research》 SCIE CAS 2025年第4期1153-1163,共11页
Our previous studies have reported that activation of the NLRP3(NOD-,LRR-and pyrin domain-containing protein 3)-inflammasome complex in ethanol-treated astrocytes and chronic alcohol-fed mice could be associated with ... Our previous studies have reported that activation of the NLRP3(NOD-,LRR-and pyrin domain-containing protein 3)-inflammasome complex in ethanol-treated astrocytes and chronic alcohol-fed mice could be associated with neuroinflammation and brain damage.Mesenchymal stem cell-derived extracellular vesicles(MSC-EVs)have been shown to restore the neuroinflammatory response,along with myelin and synaptic structural alterations in the prefrontal cortex,and alleviate cognitive and memory dysfunctions induced by binge-like ethanol treatment in adolescent mice.Considering the therapeutic role of the molecules contained in mesenchymal stem cell-derived extracellular vesicles,the present study analyzed whether the administration of mesenchymal stem cell-derived extracellular vesicles isolated from adipose tissue,which inhibited the activation of the NLRP3 inflammasome,was capable of reducing hippocampal neuroinflammation in adolescent mice treated with binge drinking.We demonstrated that the administration of mesenchymal stem cell-derived extracellular vesicles ameliorated the activation of the hippocampal NLRP3 inflammasome complex and other NLRs inflammasomes(e.g.,pyrin domain-containing 1,caspase recruitment domain-containing 4,and absent in melanoma 2,as well as the alterations in inflammatory genes(interleukin-1β,interleukin-18,inducible nitric oxide synthase,nuclear factor-kappa B,monocyte chemoattractant protein-1,and C–X3–C motif chemokine ligand 1)and miRNAs(miR-21a-5p,miR-146a-5p,and miR-141-5p)induced by binge-like ethanol treatment in adolescent mice.Bioinformatic analysis further revealed the involvement of miR-21a-5p and miR-146a-5p with inflammatory target genes and NOD-like receptor signaling pathways.Taken together,these findings provide novel evidence of the therapeutic potential of MSC-derived EVs to ameliorate the hippocampal neuroinflammatory response associated with NLRP3 inflammasome activation induced by binge drinking in adolescence. 展开更多
关键词 ADOLESCENCE binge-like ethanol treatment extracellular vesicles hippocampus mesenchymal stem cells neuroinflammation NOD- LRR-and pyrin domain-containing protein 3(NLRP3)
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A Fusion Neutron Source Driven Sub-Critical Nuclear Energy System: A Way for Early Application of Fusion Technology 被引量:11
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作者 吴宜灿 《Plasma Science and Technology》 SCIE EI CAS CSCD 2001年第6期1085-1092,共8页
This paper proposes a sub-critical nuclear energy system driven by fusion neutron source, FDS, which can be used to transmute long-lived radioactive wastes and to produce fissile nuclear fuel as a way for early applic... This paper proposes a sub-critical nuclear energy system driven by fusion neutron source, FDS, which can be used to transmute long-lived radioactive wastes and to produce fissile nuclear fuel as a way for early application of fusion technology. The necessity and feasibility to develop that system in China are illustrated on the basis of prediction of the demand of energy source in the first half of the 21th century, the status of current fission energy supply and the progress in fusion technology in the world. The characteristics of fusion neutron driver and the potential for transmutation of long-lived nuclear wastes and breeding of fissile nuclear fuel in a blanket are analyzed. A scenario of development steps is proposed. 展开更多
关键词 A Way for Early Application of Fusion Technology A Fusion Neutron Source Driven sub-critical Nuclear Energy System
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Recovery of oil and free fatty acids from spent bleaching earth using sub-critical water technology supported with kinetic and thermodynamic study 被引量:3
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作者 Rehab Abdel Fattah N. A. Mostafa +1 位作者 Mohamed S. Mahmoud Wael Abdelmoez 《Advances in Bioscience and Biotechnology》 2014年第3期261-272,共12页
This work represents the extraction of oil with high free fatty acid content from spent bleaching earth using sub-critical water technology as a greener production pathway. The extraction efficiencies under different ... This work represents the extraction of oil with high free fatty acid content from spent bleaching earth using sub-critical water technology as a greener production pathway. The extraction efficiencies under different conditions were investigated. The studied parameters include temperatures in the range of 180 to 270°C, the feed to solventfeed-to-solvent (in this case water) ratio (1:1, 1:2, 1:3, 1:4 and 1:5) and extraction times in the range of 5-60 minutes. The results showed that the optimum temperature, feed to solventfeed-to-solvent ratio, and extraction time were 270°C, 1:3, and 20 minutes, respectively. In another experiment, the extracted free fatty acids were converted into mono-, di-, and triglycerides through esterification with glycerol to increase the value added of the extracted products. The kinetics of the extraction process was found to be corresponding to an irreversible consecutive unimolecular-type first order reaction, consisting of the extraction step followed by the decomposition reaction step. Both reaction rates of extraction and decomposition were estimated using the reaction rate equations utilizing the nonlinear regression method. The apparent activation energy was calculated to be 46.1 kJ·mol-1. This result indicates a diffusion controlled reaction. For more exploration and deep understanding of the extraction mechanism, other thermodynamic parameters were also calculated and analyzed including,ΔH#, ΔS#, and ΔG# of the extraction step. 展开更多
关键词 SPENT BLEACHING Earth sub-critical Water Technology Kinetics of Extraction THERMODYNAMIC Parameters
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Law governing strata and ground movement due to sub-critical extraction 被引量:1
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作者 DAI Hua-yang~(1,2), WANG Jin-zhuang~1, CAI Mei-feng~2, YANG Ling~3 (1. China University of Mining and Technology Beijing Campus, Beijing 100083, China 2. Beijing, University of Science and Technology Beijing 100083, China 3. Central Coal Research Institute, Tangshan Branch, Tangshan 063012, China) 《中国有色金属学会会刊:英文版》 CSCD 2005年第S1期58-61,共4页
The strata movement induced by sub-critical extraction is a problem not receiving due attention because of its relatively small magnitude of deformation. However, with the increase of mining depth, sub-critical extrac... The strata movement induced by sub-critical extraction is a problem not receiving due attention because of its relatively small magnitude of deformation. However, with the increase of mining depth, sub-critical extraction has become a general phenomenon. This calls for an in-depth investigation into the characteristics of ground movements observed under different extents of sub-critical extraction, so as to determine the appropriate mining technique for use. Following a discussion of the factors influencing the extent of super-critical extraction, the super-critical extraction extent evaluation criteria was presented, the characteristics and laws of the strata and ground movements caused by such an extraction condition were systematically analyzed, and the mechanism of surface subsidence induced by sub-critical extraction was revealed. The result of study may serve as a basis for the development of the strata and ground movement prediction model and the mining techniques appropriate for use at depth beneath surface structures and buildings. 展开更多
关键词 sub-critical EXTRACTION STRATA and ground MOVEMENT extent of mining evaluation criteria.
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Fouling process and anti-fouling mechanisms of dynamic membrane assisted by photocatalytic oxidation under sub-critical fluxes 被引量:1
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作者 Tao Yang Fen Liu +3 位作者 Houfeng Xiong Qiyong Yang Fushan Chen Changchao Zhan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第8期1798-1806,共9页
Membrane fouling is often considered as a hindrance for the application of microfiltration/ultrafiltration(MF/UF) for drinking water production. A novel process of photocatalytic membrane reactor/dynamic membrane(PMR/... Membrane fouling is often considered as a hindrance for the application of microfiltration/ultrafiltration(MF/UF) for drinking water production. A novel process of photocatalytic membrane reactor/dynamic membrane(PMR/DM), operating in a continuous mode under sub-critical flux, was proposed for the mitigation of membrane fouling caused by humic acids(HAs) in water. The mechanism of membrane fouling alleviation with synergistic photocatalytic oxidation and dynamic layer isolating effect was comprehensively investigated from the characterization of foulant evolution responsible for the reversible and irreversible fouling. The results showed that the PMR/DM utilized photocatalytic oxidation to enhance the porosity and hydrophilicity of the fouling layer by converting the high molecular weight(MW) and hydrophobic HA molecules with carboxylic functional groups and aromatic structures into low-MW hydrophilic or transphilic fractions, including tryptophan-like or fulvic-like substances. The fouling layer formed in the PMR/DM by combination of photocatalytic oxidation and DM running at a sub-critical flux of 100 L·h^-1·m^-2, was more hydrophilic and more porous, resulting in the lowest trans-membrane pressure(TMP) growth rates, as compared to the processes of ceramic membrane(CM), DM and PMR/CM.Meanwhile, the dynamic layer prevented the foulants, particularly the high-MW hydrophobic fractions,from contacting the primary membrane, which enabled the membrane permeability to be restored easily. 展开更多
关键词 Dynamic MEMBRANE Photocatalytic MEMBRANE reactor HUMIC ACIDS MEMBRANE FOULING sub-critical flux
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In-plane shear(ModeⅡ) crack sub-critical propagation of rock at high temperature 被引量:1
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作者 饶秋华 谢海峰 谢强 《Journal of Central South University》 SCIE EI CAS 2008年第S1期402-405,共4页
In-plane shear crack sub-critical propagation of rock at high temperature was studied by finite element method and shear-box(i.e.compression-shear) test with newly designed electrically conductive adhesive method.Nume... In-plane shear crack sub-critical propagation of rock at high temperature was studied by finite element method and shear-box(i.e.compression-shear) test with newly designed electrically conductive adhesive method.Numerical and experimental results show that the normalized shear(Mode Ⅱ) stress intensity factors,K ⅡT/KT0 is decreased as the temperature increases because high temperature can improve stress distribution at crack tip and reduce the Mode Ⅱ stress intensity factor.Microscopic features of fractured surface are of little pits and secondary micro-cracks in the vicinity(1.5-4.0 mm) of the crack tip.The chevron-shape secondary cracks gradually merge in the length of about 4-5 mm and disappear along the direction of crack propagation.Stable shear crack propagation time is increased with the increasing temperature while the stable shear crack propagation rate is decreased with the increasing temperature,since high temperature can increase the shear(Mode Ⅱ) fracture toughness and prevent the crack growth.It is necessary to ensure the ligament of specimen long enough to measure the maximum unstable crack propagation rate of rock. 展开更多
关键词 sub-critical CRACK PROPAGATION temperature shear(Mode Ⅱ) fracture electrically CONDUCTIVE adhesive ROCK
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Effect of holes on in-plane shear(Mode Ⅱ) crack sub-critical propagation of rock 被引量:1
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作者 谢海峰 饶秋华 +2 位作者 谢强 黎纵宇 王志 《Journal of Central South University》 SCIE EI CAS 2008年第S1期453-456,共4页
Shear-box(i.e.compression-shear) test and newly designed electrically conductive adhesive method were used to measure shear crack sub-critical propagation time and rate of sandstone specimen.Different cubic specimens ... Shear-box(i.e.compression-shear) test and newly designed electrically conductive adhesive method were used to measure shear crack sub-critical propagation time and rate of sandstone specimen.Different cubic specimens with and without holes were tested to study the effect of holes on the shear crack sub-critical propagation.Numerical and experimental results show that three independent variables of hole,the interval distance S,the distance between the center of hole and the crack tip L,and hole radius R,have different contribution to the ratio of stress intensity factor of the specimen with holes to that of the specimen without hole,KⅡ/KⅡ0.Increasing S and decreasing L and R will result in the decrease of KⅡ/KⅡ0 and help crack arrest.The weight relation of the independent variables for KⅡ/KⅡ0 is S>L>R.The specimen DH3 with the largest value of S and the smallest values of L and R has the longest sub-critical crack propagation time and the smallest sub-critical crack propagation rate.Adding two suitable holes symmetrically to the original crack plane in rock specimen is considered to be a potential method for crack arrest of rock. 展开更多
关键词 sub-critical CRACK PROPAGATION hole shear(Mode Ⅱ) fracture electrically conductive adhesive ROCK
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Sub-Criticality Measurement with Source Term for Research Reactor in Inverse Kinetics Method 被引量:1
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作者 N. Jahan M. M. Rahman +1 位作者 M. Q. Huda S. M. Seo 《World Journal of Nuclear Science and Technology》 2017年第3期129-135,共7页
In reactor physics tests, it is important to monitor sub-criticality continuously during criticality approach. Reactivity measurements by the inverse kinetics method are widely used during the operation of a nuclear r... In reactor physics tests, it is important to monitor sub-criticality continuously during criticality approach. Reactivity measurements by the inverse kinetics method are widely used during the operation of a nuclear reactor. This technique is successfully applied at sufficiently high power level or to a core without an external neutron source where the neutron source term in point reactor kinetics equations may be neglected. For operation at low power levels or in the sub-critical domain, the increase in the fluctuation of the neutron signal may cause difficulties in the evaluation of reactivity and the effect of direct emission from the external neutron source may not be neglected. Therefore, contribution of the neutron source must be taken into account and this implies knowledge of a quantity proportional to the source strength, which calls the source term and then it should be determined. The research work has been conducted to measure reactivity with source term using a dedicated reactivity measurement system by the Least Square Inverse Kinetics Method (LSIKM). Application to a simulator of HANARO research reactor, Korea Atomic Energy Research Institute (KAERI), with known source strength and reactivity worth has showed consistent and satisfactory agreement. 展开更多
关键词 Source Strength sub-critical REACTIVITY REACTOR KINETICS INVERSE KINETICS Method
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Application of Sub-Critical Water Extraction in Pharmaceutical Industry
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作者 Xiaoxia Liang Qiaojia Fan 《Journal of Materials Science and Chemical Engineering》 2013年第5期1-6,共6页
Sub-critical water extraction is a brand-new separation technology. This paper mainly discussed the principle, advantages of sub-critical water extraction, and its applications ranging from the medicinal plants tradit... Sub-critical water extraction is a brand-new separation technology. This paper mainly discussed the principle, advantages of sub-critical water extraction, and its applications ranging from the medicinal plants traditionally used in Europe and Asia to produce pharmaceutical extracts (such as volatile oil, tannins, flavonoids, anthraquinone, lactone, etc.). Meanwhile, the prospect of sub-critical water extraction in plant extractives is also explored. It will be widely used in the field of medical plants, bringing huge economic benefits, environmental benefits and social benefits. 展开更多
关键词 sub-critical WATER EXTRACTION PHARMACEUTICAL EXTRACTS APPLICATION
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Technical Study on Extraction of Procyanidins in Lycium ruthenicum Murr. Using Sub-critical Fluid 1,1,1,2-Tetrafluoroethane( R134a)and Content Determination from Different Producing Areas
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作者 Liang TAN Li ZHU Zhihao FENG 《Medicinal Plant》 CAS 2018年第5期36-40,44,共6页
[Objectives] To study the optimal conditions for extracting procyanidins fromLycium ruthenicum Murr. with sub-critical fluid R134 a( 1,1,1,2-tetrafluoroethane) in 1 L extraction kettle. [Methods]Taking the extraction ... [Objectives] To study the optimal conditions for extracting procyanidins fromLycium ruthenicum Murr. with sub-critical fluid R134 a( 1,1,1,2-tetrafluoroethane) in 1 L extraction kettle. [Methods]Taking the extraction rate of procyanidins as an indicator,the influence of pressure,temperature,and extraction time on extraction rate of procyanidins fromL. Ruthenicum Murr. was studied by single factor experimental methods and orthogonal array design. [Results]The order of factors affecting extraction rate of procyanidins was extraction temperature > extraction pressure > extraction time. The optimum extraction conditions were as follows: the extraction rate of procyanidins fromL. ruthenicum Murr. was the highest with extraction pressure of 1. 2 MPa,extraction temperature of 50℃ and extraction time of 90 min. The content of procyanidins in L. ruthenicum Murr. from different producing areas was determined by vanillin-HCl method under the optimal conditions. [Conclusions] The method has the advantages of easy operation,good selectivity,low extraction temperature and high extraction efficiency,which is suitable for extraction of procyanidins in L. ruthenicum Murr. 展开更多
关键词 Lycium ruthenicum Murr. PROCYANIDINS sub-critical FLUID EXTRACTION technology R134A Vanillin-HCl method DIFFERENT producing areas Content determination
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Ethanol changes Nestin-promoter induced neural stem cells to disturb newborn dendritic spine remodeling in the hippocampus of mice 被引量:1
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作者 Guixiang Wang Wenjia Wang +7 位作者 Ye Zhang Xiaoying Gou Qingqing Zhang Yanmiao Huang Kuo Zhang Haotian Zhang Jingyu Yang Yuting Li 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期416-424,共9页
Adolescent binge drinking leads to long-lasting disorders of the adult central nervous system,particularly aberrant hippocampal neurogenesis.In this study,we applied in vivo fluorescent tracing using NestinCreERT2::Ro... Adolescent binge drinking leads to long-lasting disorders of the adult central nervous system,particularly aberrant hippocampal neurogenesis.In this study,we applied in vivo fluorescent tracing using NestinCreERT2::Rosa26-tdTomato mice and analyzed the endogenous neurogenesis lineage progression of neural stem cells(NSCs)and dendritic spine formation of newborn neurons in the subgranular zone of the dentate gyrus.We found abnormal orientation of tamoxifen-induced tdTomato+(tdTom^(+))NSCs in adult mice 2 months after treatment with EtOH(5.0 g/kg,i.p.)for 7 consecutive days.EtOH markedly inhibited tdTom^(+)NSCs activation and hippocampal neurogenesis in mouse dentate gyrus from adolescence to adulthood.EtOH(100 mM)also significantly inhibited the proliferation to 39.2%and differentiation of primary NSCs in vitro.Adult mice exposed to EtOH also exhibited marked inhibitions in dendritic spine growth and newborn neuron maturation in the dentate gyrus,which was partially reversed by voluntary running or inhibition of the mammalian target of rapamycinenhancer of zeste homolog 2 pathway.In vivo tracing revealed that EtOH induced abnormal orientation of tdTom+NSCs and spatial misposition defects of newborn neurons,thus causing the disturbance of hippocampal neurogenesis and dendritic spine remodeling in mice. 展开更多
关键词 ADOLESCENCE ADULTHOOD ethanol dentate gyrus EZH2 in vivo tracing lineage progression mTOR neural stem cell newborn dendritic spine newborn neurons
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Albizzia chinensis(Osbeck)Merr extract YS ameliorates ethanol-induced acute gastric ulcer injury in rats by regulating NRF2 signaling pathway
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作者 Bo Tang Liangning Li +4 位作者 Yuanzhi Yu Guibin Wang Shuanggang Ma Shishan Yu Jianjun Zhang 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第3期275-282,共8页
Background:Around the world,there is a high incidence of gastric ulcers.YS,an extract from the Chinese herb Albizzia chinensis(Osbeck)Merr,has potential therapeutic applications for gastrointestinal diseases.Here we e... Background:Around the world,there is a high incidence of gastric ulcers.YS,an extract from the Chinese herb Albizzia chinensis(Osbeck)Merr,has potential therapeutic applications for gastrointestinal diseases.Here we elucidated the protective effect and underlying mechanism of action of YS on gastric ulcer in rats injured by ethanol.Methods:The ethanol-i nduced gastric ulcer rat model was used to assess the protective effect of YS.A pathological examination of gastric tissue was performed by H&E staining.GES-1 cells damaged by hydrogen peroxide were used to simulate oxidative damage in gastric mucosal epithelial cells.Endogenous NRF2 was knocked down using small interfering RNA.Immunoprecipitation was used to detect ubiquitination of NRF2.Co-i mmunoprecipitation was used to detect the NRF2-Keap1 interaction.Results:YS(10 and 30 mg/kg,i.g.)significantly reduced the ulcer index,decreased MDA level,and increased SOD and GSH levels in gastric tissues damaged by ethanol.YS promoted NRF2 translocation from cytoplasm to nucleus and enhanced the NQO1 and HO-1 expression levels in injured rat gastric tissue.In addition,YS regulated NQO1 and HO-1 via NRF2 in H_(2)O_(2)-i nduced oxidative injured GES-1 cells.Further studies on the underlying mechanism indicated that YS reduced the interaction between NRF2 and Keap1 and decreased ubiquitylation of NRF2,thereby increasing its stability and expression of downstream factors.NRF2 knockdown abolished the effect of YS on MDA and SOD in GES-1 cells treated with H_(2)O_(2).Conclusion:YS reduced the NRF2-Keap1 interaction,promoting NRF2 translocation into the nucleus,which increasing the transcription and translation of NQO1 and HO-1 and improved the antioxidant capacity of rat stomach. 展开更多
关键词 ANTIOXIDATIVE ethanol gastric ulcer NRF2 YS
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Recent advances in Ni-based catalysts for the electrochemical oxidation of ethanol
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作者 Xing Tan Shiming Chen +5 位作者 Dafeng Yan Ruixing Du Qitong Zhong Longfei Liao Zhenchen Tang Feng Zeng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期588-614,共27页
The electrochemical ethanol oxidation reaction(EOR) plays a crucial role in electrochemical hydrogen production and direct ethanol fuel cells, both vital for utilizing renewable energies. Ni-based catalysts are pivota... The electrochemical ethanol oxidation reaction(EOR) plays a crucial role in electrochemical hydrogen production and direct ethanol fuel cells, both vital for utilizing renewable energies. Ni-based catalysts are pivotal in enabling efficient EOR, leading to the formation of acetic acid/acetaldehyde or CO_(2). These can serve as alternative anodic oxidation reactions for oxygen evolution reaction(OER) in water electrolysis or the anodic reaction for direct ethanol fuel cells, respectively. This review explores recent advancements in EOR over Ni-based catalysts. It begins with an overview of EOR performance across various Ni-based catalysts, followed by an examination of the reaction chemistry, mechanism, and active sites.The review then delves into strategies for designing highly active Ni-based EOR catalysts. These strategies include promotion with transition metals, noble metals, nonmetals, and carbon materials, as well as creating amorphous structures, special morphologies, and single-atom catalysts. Additionally, it discusses the concept of self-supporting catalysts using three-dimensional porous substrates. Finally, the review highlights emerging methodologies that warrant further exploration, along with future directions for designing highly active and stable EOR catalysts. 展开更多
关键词 ethanol oxidation NICKEL Water electrolysis Fuel cell
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Microchannel reactive distillation for the conversion of aqueous ethanol to ethylene
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作者 Johnny Saavedra-Lopez Stephen D.Davidson +6 位作者 Paul H.Humble Dan R.Bottenus Vanessa Lebarbier Dagle Yuan Jiang Charles J.Freeman Ward E.Te Grotenhuis Robert A.Dagle 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期481-493,共13页
Here we demonstrate the proof-of-concept for microchannel reactive distillation for alcohol-to-jet application:combining ethanol/water separation and ethanol dehydration in one unit operation.Ethanol is first distille... Here we demonstrate the proof-of-concept for microchannel reactive distillation for alcohol-to-jet application:combining ethanol/water separation and ethanol dehydration in one unit operation.Ethanol is first distilled into the vapor phase,converted to ethylene and water,and then the water co-product is condensed to shift the reaction equilibrium.Process intensification is achieved through rapid mass transfer-ethanol stripping from thin wicks using novel microchannel architectures-leading to lower residence time and improved separation efficiency.Energy savings are realized with integration of unit operations.For example,heat of condensing water can offset vaporizing ethanol.Furthermore,the dehydration reaction equilibrium shifts towards completion by immediate removal of the water byproduct upon formation while maintaining aqueous feedstock in the condensed phase.For aqueous ethanol feedstock(40%_w),71% ethanol conversion with 91% selectivity to ethylene was demonstrated at 220℃,600psig,and 0.28 h^(-1) wt hour space velocity.2.7 stages of separation were also demonstrated,under these conditions,using a device length of 8.3 cm.This provides a height equivalent of a theoretical plate(HETP),a measure of separation efficiency,of ^(3).3 cm.By comparison,conventional distillation packing provides an HETP of ^(3)0 cm.Thus,9,1 × reduction in HETP was demonstrated over conventional technology,providing a means for significant energy savings and an example of process intensification.Finally,preliminary process economic analysis indicates that by using microchannel reactive distillation technology,the operating and capital costs for the ethanol separation and dehydration portion of an envisioned alcoholto-jet process could be reduced by at least 35% and 55%,respectively,relative to the incumbent technology,provided future improvements to microchannel reactive distillation design and operability are made. 展开更多
关键词 Catalytic distillation ethanol dehydration Process intensification MICROCHANNEL Alcohol-to-jet process
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Impact of ethanol on the flotation efficiency of imidazolium ionic liquids as collectors:Insights from dynamic surface tension and solvation analysis
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作者 Qian Cheng Zerui Lei +1 位作者 Guangjun Mei Jianhua Chen 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第12期2645-2656,共12页
To conduct extensive research on the application of ionic liquids as collectors in mineral flotation,ethanol(EtOH)was used as a solvent to dissolve hydrophobic ionic liquids(ILs)to simplify the reagent regime.Interest... To conduct extensive research on the application of ionic liquids as collectors in mineral flotation,ethanol(EtOH)was used as a solvent to dissolve hydrophobic ionic liquids(ILs)to simplify the reagent regime.Interesting phenomena were observed in which EtOH exerted different effects on the flotation efficiency of two ILs with similar structures.When EtOH was used to dissolve 1-dodecyl-3-methylimidazolium chloride(C12[mim]Cl)and as a collector for pure quartz flotation tests at a concentration of 1×10^(−5)mol·L^(−1),quartz recovery increased from 23.77%to 77.91%compared with ILs dissolved in water.However,quartz recovery of 1-dodecyl-3-methylim-idazolium hexafluorophosphate(C12[mim]PF6)decreased from 60.45%to 24.52%under the same conditions.The conditional experi-ments under 1×10^(−5)mol·L^(−1)ILs for EtOH concentration and under 2vol%EtOH for ILs concentration confirmed this difference.After being affected by EtOH,the mixed ore flotation tests of quartz and hematite showed a decrease in the hematite concentrate grade and re-covery for the C12[mim]Cl collector,whereas the hematite concentrate grade and recovery for the C12[mim]PF6 collector increased.On the basis of these differences and observations of flotation foam,two-phase bubble observation tests were carried out.The EtOH promoted the foam height of two ILs during aeration.It accelerated static froth defoaming after aeration stopped,and the foam of C12[mim]PF6 de-foaming especially quickly.In the discussion of flotation tests and foam observation,an attempt was made to explain the reasons and mechanisms behind the diverse phenomena using the dynamic surface tension effect and solvation effect results from EtOH.The solva-tion effect was verified through Fourier transform infrared(FT-IR),X-ray photoelectron spectroscopy(XPS),and Zeta potential tests.Al-though EtOH affects the adsorption of ILs on the ore surface during flotation negatively,it holds an positive value of inhibiting foam mer-ging during flotation aeration and accelerating the defoaming of static foam.And induce more robust secondary enrichment in the mixed ore flotation of the C12[mim]PF6 collector,facilitating effective mixed ore separation even under inhibitor-free conditions. 展开更多
关键词 ionic liquid ethanol flotation foam SOLVATION dynamic surface tension
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Validation of a Method for Characterization of Ethanol in Water by HS-GC-FID to Serve the Traceability of Halal Measurements
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作者 Adel B. Shehata Abdulrahman R. Al Askar +3 位作者 Mohammed A. Al Rasheed Abdulrahman M. Al Zahrany Fahd A. Al Kharraa Sowailem A. Al Sowailem 《Green and Sustainable Chemistry》 2024年第2期17-28,共12页
The determination of the ethanol content in food products is of fundamental importance for HALAL certification. In this work, an analytical method for the determination of ethanol in water by headspace gas chromatogra... The determination of the ethanol content in food products is of fundamental importance for HALAL certification. In this work, an analytical method for the determination of ethanol in water by headspace gas chromatography with flame ionization detector (HS-GC-FID) has been developed and validated for the use in characterization of ethanol reference materials. The validation study was carried out in the linear calibration range 100 - 1500 mg/kg using the NIST SRM 2900, nominal 95.6%. The studied performance characteristics of the method were the limit of detection, LOD, the limit of quantification LOQ, selectivity, linearity, precision, recovery and bias. The validation results showed that the method is selective, precise, accurate and free from any significant bias. The LOD and LOQ were 1.27 and 3.86 mg/kg respectively and the estimated expanded uncertainty was 2% indicating that the method is fit for the purpose of certification of ethanol in water reference materials. 展开更多
关键词 ethanol HS-GC-FID VALIDATION LINEARITY Precision Bias
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Tailoring Ni based catalysts by indium for the dehydrogenative coupling of ethanol into ethyl acetate
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作者 Ming Yin Jifeng Pang +4 位作者 Jin Guo Xianquan Li Yujia Zhao Pengfei Wu Mingyuan Zheng 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第8期1321-1331,共11页
Exploring stable and robust catalysts to replace the current toxic CuCr based catalysts for dehydrogenative coupling of ethanol to ethyl acetate is a challenging but promising task.Herein,novel NiIn based catalysts we... Exploring stable and robust catalysts to replace the current toxic CuCr based catalysts for dehydrogenative coupling of ethanol to ethyl acetate is a challenging but promising task.Herein,novel NiIn based catalysts were developed by tailoring Ni catalysts with Indium(In)for this reaction.Over the optimal Ni0.1Zn0.7Al0.3InOx catalyst,the ethyl acetate selectivity reached 90.1%at 46.2%ethanol conversion under the conditions of 548 K and a weight hourly space velocity of 1.9 h^(-1)in the 370 h time on stream.Moreover,the ethyl acetate productivity surpassed 1.1 g_(ethyl acetate)g_(catalyst)^(-1)h^(-1),,one of the best performance in current works.According to catalyst characterizations and conditional experiments,the active sites for dehydrogenative coupling of ethanol to ethyl acetate were proved to be Ni4In alloys.The presence of In tailored the chemical properties of Ni,and subsequently inhibited the C-C cracking and/or condensation reactions during ethanol conversions.Over Ni4In alloy sites,ethanol was dehydrogenated into acetaldehyde,and then transformed into acetyl species with the removal of H atoms.Finally,the coupling between acetyl species and surface-abundant ethoxyde species into ethyl acetate was achieved,affording a high ethyl acetate selectivity and catalyst stability. 展开更多
关键词 Dehydrogenative coupling ethanol Ethyl acetate Nickel and indium alloys
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Dendrobium offi cinale flowers flavonoids enriched extract protects against acute ethanol-induced gastric ulcers via AMPK/PI3K signaling pathways
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作者 Zhiyu Zhang Hualing Xie +3 位作者 Mohamed A.Farag Zhenhao Li Qingping Wu Ping Shao 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第6期3661-3679,共19页
Gastric ulcer is a widespread disease caused by various etiologies.Dendrobium offi cinale flowers exert several health benefits owing to their rich flavonoid content.In this study,protective effects and possible actio... Gastric ulcer is a widespread disease caused by various etiologies.Dendrobium offi cinale flowers exert several health benefits owing to their rich flavonoid content.In this study,protective effects and possible action mechanisms of D.offi cinale flowers’flavonoid enriched extract(DOFF)were assessed against gastric ulcer.The result of sodium nitrite-aluminum nitrate colorimetry showed that 52.34%of the total extractive was flavonoid,and ultra-high performance liquid chromatography time of flight mass spectrometer(UPLC-QTOF/MS)revealed the presence of 28 components in DOFF of which 14 belonged to flavonoids.In addition,in vivo assay revealed DOFF potential in reducing the formation of ethanol-induced gastric mucosal lesions,with drop-in ulcer index from 64.33±8.76 to 32.00±4.47.Similar results were revealed in human gastric mucosal epithelia cells,with cells viability to increase from 27.2%to 61.6%post DOFF administration.To analyzed the protect effect of DOFF,we used Western blotting and immunofluorometric assay to revealed the expression levels of key proteins in cell pathways.The results showed that DOFF(320μg/mL)could increase the level of oxidation marker protein(HO-1),apoptosis regulatory protein(Bcl-2)and autophagy marker(LC3β)by 50.84%,43.85%,and 59.21%compared with ethanol-treated group respectively.Further analyzed of the mitochondrial activity and apoptosis pathway,we found that DOFF appeared to mitigate against ethanolinduced gastric mucosal injury via AMPK/mTOR/ULK1 and PI3K/AKT autophagy signaling pathways. 展开更多
关键词 Dendrobium offi cinale flower ethanol FLAVONOIDS Gastric injury Autophagy
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